diff --git a/src/repositories/shuttle/eta/BaseRedisETARepository.ts b/src/repositories/shuttle/eta/BaseRedisETARepository.ts
new file mode 100644
index 0000000..13da39e
--- /dev/null
+++ b/src/repositories/shuttle/eta/BaseRedisETARepository.ts
@@ -0,0 +1,62 @@
+import { IEta } from "../../../entities/ShuttleRepositoryEntities";
+import { BaseRedisRepository } from "../../BaseRedisRepository";
+import { ETAGetterRepository, ETARepositoryEventListener, ETARepositoryEventName } from "./ETAGetterRepository";
+
+export abstract class BaseRedisETARepository extends BaseRedisRepository implements ETAGetterRepository {
+  getEtasForShuttleId(shuttleId: string): Promise<IEta[]> {
+    throw new Error("Method not implemented.");
+  }
+
+  getEtasForStopId(stopId: string): Promise<IEta[]> {
+    throw new Error("Method not implemented.");
+  }
+
+  getEtaForShuttleAndStopId(shuttleId: string, stopId: string): Promise<IEta | null> {
+    throw new Error("Method not implemented.");
+  }
+
+  // EventEmitter override methods for type safety
+  override on<T extends ETARepositoryEventName>(
+    event: T,
+    listener: ETARepositoryEventListener<T>,
+  ): this;
+  override on(event: string | symbol, listener: (...args: any[]) => void): this {
+    return super.on(event, listener);
+  }
+
+  override once<T extends ETARepositoryEventName>(
+    event: T,
+    listener: ETARepositoryEventListener<T>,
+  ): this;
+  override once(event: string | symbol, listener: (...args: any[]) => void): this {
+    return super.once(event, listener);
+  }
+
+  override off<T extends ETARepositoryEventName>(
+    event: T,
+    listener: ETARepositoryEventListener<T>,
+  ): this;
+  override off(event: string | symbol, listener: (...args: any[]) => void): this {
+    return super.off(event, listener);
+  }
+
+  override addListener<T extends ETARepositoryEventName>(
+    event: T,
+    listener: ETARepositoryEventListener<T>,
+  ): this;
+  override addListener(event: string | symbol, listener: (...args: any[]) => void): this {
+    return super.addListener(event, listener);
+  }
+
+  override removeListener<T extends ETARepositoryEventName>(
+    event: T,
+    listener: ETARepositoryEventListener<T>,
+  ): this;
+  override removeListener(event: string | symbol, listener: (...args: any[]) => void): this {
+    return super.removeListener(event, listener);
+  }
+
+  override removeAllListeners(eventName?: string | symbol): this {
+    return super.removeAllListeners(eventName);
+  }
+}
diff --git a/src/repositories/shuttle/eta/RedisExternalSourceETARepository.ts b/src/repositories/shuttle/eta/RedisExternalSourceETARepository.ts
index 033dc2e..3dac564 100644
--- a/src/repositories/shuttle/eta/RedisExternalSourceETARepository.ts
+++ b/src/repositories/shuttle/eta/RedisExternalSourceETARepository.ts
@@ -1,40 +1,13 @@
 import { IEta } from "../../../entities/ShuttleRepositoryEntities";
-import { BaseRedisRepository } from "../../BaseRedisRepository";
-import { ETARepositoryEventName, ETARepositoryEventListener } from "./ETAGetterRepository";
+import { BaseRedisETARepository } from "./BaseRedisETARepository";
 import { ExternalSourceETARepository } from "./ExternalSourceETARepository";
 
-export class RedisExternalSourceETARepository extends BaseRedisRepository implements ExternalSourceETARepository {
+export class RedisExternalSourceETARepository extends BaseRedisETARepository implements ExternalSourceETARepository {
   addOrUpdateEtaFromExternalSource(eta: IEta): Promise<void> {
     throw new Error("Method not implemented.");
   }
+
   removeEtaIfExists(shuttleId: string, stopId: string): Promise<IEta | null> {
     throw new Error("Method not implemented.");
   }
-  on<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  once<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  off<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  addListener<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  removeListener<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  getEtasForShuttleId(shuttleId: string): Promise<IEta[]> {
-    throw new Error("Method not implemented.");
-  }
-  getEtasForStopId(stopId: string): Promise<IEta[]> {
-    throw new Error("Method not implemented.");
-  }
-  getEtaForShuttleAndStopId(shuttleId: string, stopId: string): Promise<IEta | null> {
-    throw new Error("Method not implemented.");
-  }
-  removeAllListeners(eventName?: string | symbol | undefined): this {
-    throw new Error("Method not implemented.");
-  }
 }
diff --git a/src/repositories/shuttle/eta/RedisSelfUpdatingETARepository.ts b/src/repositories/shuttle/eta/RedisSelfUpdatingETARepository.ts
index d9aac9f..3a84d7d 100644
--- a/src/repositories/shuttle/eta/RedisSelfUpdatingETARepository.ts
+++ b/src/repositories/shuttle/eta/RedisSelfUpdatingETARepository.ts
@@ -1,12 +1,10 @@
-import { IEta } from "../../../entities/ShuttleRepositoryEntities";
-import { ETARepositoryEventName, ETARepositoryEventListener } from "./ETAGetterRepository";
 import { SelfUpdatingETARepository } from "./SelfUpdatingETARepository";
-import { BaseRedisRepository } from "../../BaseRedisRepository";
+import { BaseRedisETARepository } from "./BaseRedisETARepository";
 import { createClient, RedisClientType } from "redis";
 import { ShuttleGetterRepository, ShuttleTravelTimeDataIdentifier, ShuttleTravelTimeDateFilterArguments } from "../ShuttleGetterRepository";
 import { REDIS_RECONNECT_INTERVAL } from "../../../environment";
 
-export class RedisSelfUpdatingETARepository extends BaseRedisRepository implements SelfUpdatingETARepository {
+export class RedisSelfUpdatingETARepository extends BaseRedisETARepository implements SelfUpdatingETARepository {
   constructor(
     readonly shuttleRepository: ShuttleGetterRepository,
     redisClient: RedisClientType = createClient({
@@ -20,37 +18,12 @@ export class RedisSelfUpdatingETARepository extends BaseRedisRepository implemen
   ) {
     super(redisClient);
   }
+
   getAverageTravelTimeSeconds(identifier: ShuttleTravelTimeDataIdentifier, dateFilter: ShuttleTravelTimeDateFilterArguments): Promise<number | undefined> {
     throw new Error("Method not implemented.");
   }
+
   startListeningForUpdates(): void {
     throw new Error("Method not implemented.");
   }
-  on<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  once<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  off<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  addListener<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  removeListener<T extends ETARepositoryEventName>(event: T, listener: ETARepositoryEventListener<T>): this {
-    throw new Error("Method not implemented.");
-  }
-  getEtasForShuttleId(shuttleId: string): Promise<IEta[]> {
-    throw new Error("Method not implemented.");
-  }
-  getEtasForStopId(stopId: string): Promise<IEta[]> {
-    throw new Error("Method not implemented.");
-  }
-  getEtaForShuttleAndStopId(shuttleId: string, stopId: string): Promise<IEta | null> {
-    throw new Error("Method not implemented.");
-  }
-  removeAllListeners(eventName?: string | symbol | undefined): this {
-    throw new Error("Method not implemented.");
-  }
 }